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1.
Int J Gen Med ; 17: 2371-2386, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799203

RESUMO

Purpose: There is growing evidence that the immune system plays an important role in the progression of Parkinson's disease, the second most common neurodegenerative disorder. This study aims to address the comprehensive understanding of the immunopathogenesis of Parkinson's disease and explore new inflammatory biomarkers. Patients and Methods: In this study, Immune-related differential expressed genes (DEIRGs) were obtained from GEO database and Immport database. The hub gene was screened in DEIRGs using LASSO regression and random forest algorithm, and the mRNA expression of the identified hub gene was validated using clinical blood samples. Results: We obtained a total of 157 DEIRGs that played an important role in the immune response. The results of immune cell infiltration analysis showed that the degree of memory B cells infiltration was higher in PD patients, while the degree of Monocytes, resting mast cells and M0 macrophages infiltration was lower (p<0.05). A total of 8 hub genes were screened by machine learning methods, and RT-PCR results showed that the expression level of CBL gene in PD was significantly increased (p<0.05). Conclusion: Our findings suggest that CBL is a new potential diagnostic biomarker for PD and that abnormal immune cell infiltration may influence PD development.

2.
Biomater Sci ; 12(10): 2717-2729, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38619816

RESUMO

Polymeric heart valves (PHVs) present a promising alternative for treating valvular heart diseases with satisfactory hydrodynamics and durability against structural degeneration. However, the cascaded coagulation, inflammatory responses, and calcification in the dynamic blood environment pose significant challenges to the surface design of current PHVs. In this study, we employed a surface-initiated polymerization method to modify polystyrene-block-isobutylene-block-styrene (SIBS) by creating three hydrogel coatings: poly(2-methacryloyloxy ethyl phosphorylcholine) (pMPC), poly(2-acrylamido-2-methylpropanesulfonic acid) (pAMPS), and poly(2-hydroxyethyl methacrylate) (pHEMA). These hydrogel coatings dramatically promoted SIBS's hydrophilicity and blood compatibility at the initial state. Notably, the pMPC and pAMPS coatings maintained a considerable platelet resistance performance after 12 h of sonication and 10 000 cycles of stretching and bending. However, the sonication process induced visible damage to the pHEMA coating and attenuated the anti-coagulation property. Furthermore, the in vivo subcutaneous implantation studies demonstrated that the amphiphilic pMPC coating showed superior anti-inflammatory and anti-calcification properties. Considering the remarkable stability and optimal biocompatibility, the amphiphilic pMPC coating constructed by surface-initiated polymerization holds promising potential for modifying PHVs.


Assuntos
Materiais Revestidos Biocompatíveis , Hidrogéis , Fosforilcolina , Propriedades de Superfície , Fosforilcolina/química , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacologia , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Teste de Materiais , Poli-Hidroxietil Metacrilato/química , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia , Metacrilatos/química , Polímeros/química , Polímeros/farmacologia , Próteses Valvulares Cardíacas , Valvas Cardíacas/efeitos dos fármacos , Humanos , Camundongos , Interações Hidrofóbicas e Hidrofílicas
3.
Psychopharmacology (Berl) ; 240(4): 713-724, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36847832

RESUMO

RATIONALE: Sepsis is a severe inflammatory response to infection that leads to long-lasting cognitive impairment and depression after resolution. The lipopolysaccharide (LPS)-induced endotoxaemia model is a well-established model of gram-negative bacterial infection and recapitulates the clinical characteristics of sepsis. However, whether LPS-induced endotoxaemia during adolescence can modulate depressive and anxiety-like behaviours in adulthood remains unclear. OBJECTIVES: To determine whether LPS-induced endotoxaemia in adolescence can modulate the stress vulnerability to depressive and anxiety-like behaviours in adulthood and explore the underlying molecular mechanisms. METHODS: Quantitative real-time PCR was used to measure inflammatory cytokine expression in the brain. A stress vulnerability model was established by exposure to subthreshold social defeat stress (SSDS), and depressive- and anxiety-like behaviours were evaluated by the social interaction test (SIT), sucrose preference test (SPT), tail suspension test (TST), force swimming test (FST), elevated plus-maze (EPM) test, and open field test (OFT). Western blotting was used to measure Nrf2 and BDNF expression levels in the brain. RESULTS: Our results showed that inflammation occurred in the brain 24 h after the induction of LPS-induced endotoxaemia at P21 but resolved in adulthood. Furthermore, LPS-induced endotoxaemia during adolescence promoted the inflammatory response and the stress vulnerability after SSDS during adulthood. Notably, the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and BDNF in the mPFC were decreased after SSDS exposure in mice treated with LPS during adolescence. Activation of the Nrf2-BDNF signalling pathway by sulforaphane (SFN), an Nrf2 activator, ameliorated the effect of LPS-induced endotoxaemia during adolescence on stress vulnerability after SSDS during adulthood. CONCLUSIONS: Our study identified adolescence as a critical period during which LPS-induced endotoxaemia can promote stress vulnerability during adulthood and showed that this effect is mediated by impairment of Nrf2-BDNF signalling in the mPFC.


Assuntos
Endotoxemia , Fator 2 Relacionado a NF-E2 , Córtex Pré-Frontal , Animais , Camundongos , Comportamento Animal , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/metabolismo , Depressão/patologia , Endotoxemia/metabolismo , Hipocampo/metabolismo , Lipopolissacarídeos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Adolescente , Humanos , Modelos Animais de Doenças , Transdução de Sinais
4.
J Transl Med ; 20(1): 546, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435787

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) is one of the most common types of sepsis-related organ dysfunction without overt central nervous system (CNS) infection. It is associated with higher mortality, low quality of life, and long-term neurological sequelae in suspected patients. At present there is no specific treatment for SAE rather than supportive therapy and judicious use of antibiotics, which are sometimes associated with adverse effects. Molecular hydrogen (H2) has been reported to play crucial role in regulating inflammatory responses, neuronal injury, apoptosis and mitochondrial dysfunction in adult models of SAE. Here we report the protective effect of hydrogen-rich saline in juvenile SAE rat model and its possible underling mechanism(s). MATERIALS AND METHODS: Rats were challenged with lipopolysaccharide (LPS) at a dose of 8 mg/kg injected intraperitoneally to induce sepsis and hydrogen-rich saline (HRS) administered 1 h following LPS induction at a dose of 5 ml/kg. Rats were divided into: sham, sham + HRS, LPS and LPS + HRS. At 48 h, rats were sacrificed and Nissl staining for neuronal injury, TUNEL assay for apoptotic cells detection, immunohistochemistry, and ELISA protocol for inflammatory cytokines determination, mitochondrial dysfunction parameters, electron microscopy and western blot analysis were studied to examine the effect of HRS in LPS-induced septic rats. RESULTS: Rats treated with HRS improved neuronal injury, improvement in rats' survival rate. ELISA analysis showed decreased TNF-α and IL-1ß and increased IL-10 expression levels in the HRS-treated group. Apoptotic cells were decreased after HRS administration in septic rats. The numbers of GFAP and IBA-1positive cells were attenuated in the HRS-treated group when compared to the LPS group. Subsequently, GFAP and IBA-1 immunoreactivity were decreased after HRS treatment. Mitochondrial membrane potential detected by JC-1 dye and ATP content were decreased in septic rats, which were improved after HRS treatment, while release of ROS was increased in the LPS group reverted by HRS treatment, ameliorating mitochondrial dysfunction. Further analysis by transmission electron microscopy showed decreased number of mitochondria and synapses, and disrupted mitochondrial membrane ultrastructure in the LPS group, while HRS administration increased mitochondria and synapses number. CONCLUSION: These data demonstrated that HRS can improve survival rate, attenuate neuroinflammation, astrocyte and microglial activation, neuronal injury and mitochondrial dysfunction in juvenile SAE rat model, making it a potential therapeutic candidate in treating paediatric SAE.


Assuntos
Encefalopatia Associada a Sepse , Sepse , Ratos , Animais , Encefalopatia Associada a Sepse/complicações , Encefalopatia Associada a Sepse/metabolismo , Lipopolissacarídeos/farmacologia , Doenças Neuroinflamatórias , Qualidade de Vida , Ratos Sprague-Dawley , Sepse/complicações , Mitocôndrias/metabolismo , Hidrogênio/farmacologia , Hidrogênio/uso terapêutico , Hidrogênio/metabolismo
5.
Ann Palliat Med ; 11(1): 321-331, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35144423

RESUMO

BACKGROUND: In this study, we compared the efficacy of Ahmed, Ex-PRESS, and trabeculectomy to provide a reference for determining surgical schemes for glaucoma patients undergoing external drainage surgery in clinical practice. METHODS: We performed a literature search for studies on the treatment of primary and secondary glaucoma with three types of external drainage surgery (Ahmed, Ex-PRESS, and trabeculectomy). As at April 24, 2021, seven electronic databases were searched for randomized controlled trials comparing any two of Ahmed, Ex-PRESS, and trabeculectomy in the treatment of glaucoma. The Cochrane tool was also adopted to evaluate the risk of bias in these trials. The relative risk (RR) with 95% confidence interval (CI), and weighted mean difference (WMD) were determined and compared indirectly using R software. RESULTS: A total of 14 randomized controlled trials were included in this study, involving 866 eyes of 808 patients. As for the intraocular pressure (IOP) after 3 months, trabeculectomy did not contribute to better improvement than Ahmed (WMD =0.014; 95% CI: -0.14-0.18) and Ex-PRESS (WMD =0.014; 95% CI: -0.072-0.097). However, there was a significant difference in the IOP 1 year between trabeculectomy and Ex-PRESS (WMD =0.097; 95% CI: 0.0080-0.18), with the latter achieving a favorable improvement effect. Meanwhile, the complete success (CS) of trabeculectomy was significantly lower than that of Ex-PRESS (RR =0.73; 95% CI: 0.57-0.93). In addition, Ex-PRESS was superior to Ahmed (WMD =-0.48; 95% CI: -0.89 to -0.084) in terms of a decreased number of post-operative medications. DISCUSSION: For glaucoma patients who are required to receive external drainage surgery, Ex-PRESS could achieve a significant effect on the IOP 1 year and CS, as well as a marked decrease in the number of post-operative medications used, compared with the other two types of surgery. In terms of the efficacy at least 1 year after surgery, Ex-PRESS should be one of the preferred methods for external drainage.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma , Trabeculectomia , Glaucoma/cirurgia , Humanos , Pressão Intraocular , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
J Pept Sci ; 27(9): e3333, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34114290

RESUMO

Interactions between charged amino acids significantly influence the structure and function of proteins. The encoded charged amino acids Asp, Glu, Arg, and Lys have different number of hydrophobic methylenes linking the backbone to the charged functionality. It remains to be fully understood how does this difference in the number of methylenes affect protein structure stability. Protein secondary structures are the fundamental three-dimensional building blocks of protein structures. ß-Sheet structures are particularly interesting, because these structures have been associated with a number of protein misfolding diseases. Herein, we report the effect of charged amino acid side chain length at two ß-strand positions individually on the stability of a ß-hairpin. The charged amino acids include side chains with a carboxylate, an ammonium, or a guanidinium group. The experimental peptides, fully folded reference peptides, and fully unfolded reference peptides were synthesized by solid phase peptide synthesis and analyzed by 2D NMR methods including TOCSY, DQF-COSY, and ROESY. Sequence specific assignments were performed for all peptides. The chemical shift data were used to derive the fraction folded population and the folding free energy for the experimental peptides. Results showed that the fraction folded population increased with increasing charged amino acid side chain length. These results should be useful for developing functional peptides that adopt the ß-conformation.


Assuntos
Aminoácidos , Peptídeos , Conformação Proteica em Folha beta , Dobramento de Proteína , Estrutura Secundária de Proteína , Termodinâmica
7.
Org Biomol Chem ; 19(8): 1860-1866, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33565556

RESUMO

Collagen is a major structural component of the extracellular matrix and connective tissue. The key structural feature of collagen is the collagen triple helix, with a Xaa-Yaa-Gly (glycine) repeating pattern. The most frequently occurring triplet is Pro (proline)-Hyp (hydroxyproline)-Gly. The reversible thermal folding and unfolding of a series of heterotrimeric collagen triple helices with varying number of Pro-Hyp-Gly triplets were monitored by circular dichroism spectroscopy to determine the unfolding thermodynamic parameters Tm (midpoint transition temperature), ΔHTm (unfolding enthalpy), and ΔGunfold (unfolding free energy). The Tm and ΔGunfold of the heterotrimeric collagen triple helices increased with increasing number of Pro-Hyp-Gly triplets. The ΔGunfold increased by 2.0 ± 0.2 kcal mol-1 upon inserting one Pro-Hyp-Gly triplet into all three chains. The Tm difference between the most stable ABC combination and the second most stable BCC combination decreased with increasing number of Pro-Hyp-Gly triplets, even though the ΔGunfold difference remained the same. These results should be useful for tuning the stability of collagen triple helical peptides for hydrogel formation, recognition of denatured collagen triple helices as diagnostics and therapeutics, and targeted drug delivery.


Assuntos
Colágeno/metabolismo , Sequência de Aminoácidos , Colágeno/síntese química , Transição de Fase , Conformação Proteica em alfa-Hélice , Estabilidade Proteica , Estrutura Quaternária de Proteína , Desdobramento de Proteína , Termodinâmica , Temperatura de Transição
8.
Int J Ophthalmol ; 14(1): 127-132, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33469494

RESUMO

AIM: To evaluate the predicting efficacy of severe retinopathy of prematurity (ROP) by the WINROP algorithm (http://winrop.com) in Southern China. METHODS: All preterm infants with the gestational age (GA) less than 32wk were included. Their ROP screening results and serial postnatal body weight were analysed retrospectively. Weekly body weight was entered into and measured by the WINROP system. The outcomes were analysed, and the sensitivity, specificity, positive predictive value and negative predictive value (NPV) were calculated. RESULTS: Totally 432 infants with a median GA of 30.0 (24.0-31.9)wk, and a median birth weight (BW) of 1360 (540-2700) g were included. Among these 432 infants, 50 were diagnosed as type 1 ROP but only 28 were identified by the WINROP algorithm. The sensitivity was 56% (28/50) and the NPV was 92% (252/274). However, for infants with BW <1000 g or GA <28wk, the sensitivity was 93.8% (15/16) and 93.3% (14/15), respectively. Meanwhile, with several postnatal complications added as additional risk factors, the sensitivity was increased to 96% (48/50). CONCLUSION: The sensitivity of the WINROP algorithm from the Southern Chinese cohort is not as high as that reported in developed countries. This algorithm is effective for detecting severe ROP from extremely small or preterm infants. Modification of the algorithm with additional risk factors could improve the predictive value for infants with a GA>28wk in China.

9.
J Colloid Interface Sci ; 584: 225-235, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069021

RESUMO

To overcome the organic-/bio- fouling of the membrane, a dual-functional ultrafiltration membrane containing quaternary ammonium and zwitterionic polymers via quaternization and surface radical polymerization was designed, and its antifouling and antibacterial behavior was studied. In this work, poly(vinylidene fluoride)/poly(methyl methacrylate-co-dimethylamino-2-ethyl methacrylate) (PVDF/P(MMA-co-DMAEMA)) blend membrane was quaternized by p-chloromethyl styrene (p-CMS), and the double bonds were introduced onto the membrane surface, which further participated in the polymerization of zwitterionic monomers on the membrane surface. The results indicated that the resultant membrane exhibited obviously improved hydrophilicity and weak positive charge (isoelectric point, 7.49). The membrane presented higher flux recovery ratio and lower protein adhesion compared with the pure PVDF membrane. Meanwhile, the membrane showed high-efficiency broad-spectrum antibacterial performance, that is, the bacteria killing efficiency of S. aureus and E. coli reached 98.2% and 97.0%, respectively. Moreover, the membrane effectively inhibited bacterial adhesion, which is important for the long-term antibacterial properties of membrane. This antifouling and antibacterial PVDF membrane may have potential in the long-term filtration process, especially when dealing with microbiologically contaminated water.


Assuntos
Compostos de Amônio , Incrustação Biológica , Antibacterianos/farmacologia , Incrustação Biológica/prevenção & controle , Escherichia coli , Polímeros , Staphylococcus aureus
10.
J Chem Neuroanat ; 71: 13-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26698223

RESUMO

BACKGROUND: The hippocampus, central amygdaloid nucleus and the ventromedial region (marginal division) of the striatum have been reported to be involved in the mechanism of learning and memory. This study aimed elucidating anatomical and functional connections among these brain areas during learning and memory. RESULTS: In the first part of this study, the c-Fos protein was used to explore functional connections among these structures. Chemical stimulation of either hippocampus or central amygdaloid nucleus results in dense expression of c-Fos protein in nuclei of neurons in the marginal division of the striatum, indicating that the hippocampus and the central amygdaloid nucleus might be functionally connected with the marginal division. In the second part of the study, the cholera toxin subunit B-horseradish peroxidase was injected into the central amygdaloid nucleus to observe anatomical connections among them. The retrogradely transported conjugated horseradish peroxidase was observed in neurons of both the marginal division and dorsal part of the hippocampus following the injection. Hence, neural fibers from both the marginal division and the hippocampus directly projected to the central amygdaloid nucleus. CONCLUSION: The results implicated potential new functional and structural pathways through these brain areas during the process of learning and memory. The pathways ran from ventromedial portion (the marginal division) of the striatum to the central amygdaloid nucleus and then to the hippocampus before going back to the marginal division of the striatum. Two smaller circuits were between the marginal division and the central amygdaloid nucleus, and between the central amygdaloid nucleus and the hippocampus. These connections have added new dimensions of neural networks of learning and memory, and might be involved in the pathogenesis of dementia and Alzheimer disease.


Assuntos
Tonsila do Cerebelo/fisiologia , Corpo Estriado/fisiologia , Hipocampo/fisiologia , Aprendizagem , Animais , Núcleo Celular/metabolismo , Toxina da Cólera , Peroxidase do Rábano Silvestre , Masculino , Memória , Vias Neurais , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Sprague-Dawley
11.
Mol Neurobiol ; 51(2): 827-39, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25274077

RESUMO

The memory function of the hippocampal formation (Hip) and the marginal division (MrD) of neostriatum was compared. Rats with bilateral lesions of the MrD either immediate or 24 h after training in Y-maze were found to have decrease in correct runs in both groups. However, animals with transected afferent and efferent nerve bundles to isolate the Hip immediately or 24 h after training in Y-maze were found to show a decrease in correct runs only in the group injured immediately after Y-maze training but not in the 24 h group suggesting that MrD is likely involved in the entire process of long-term memory consolidation whereas the Hip only contributes to memory in the early stage. In addition, animals treated with a NMDA receptor (NMDAR) blocker, e.g. MK-801, showed decreased correct runs in Y-maze test and in expression level of phosphorylated CREB (pCREB) in neurons of the MrD but not in the Hip. Furthermore, animals treated with okadaic acid (OA), a potent protein phosphatase 1 inhibitor, showed increased correct runs in the Y-maze test. The expression level of pCREB and c-Fos and c-Jun was found increased in neurons of the MrD and the Hip in response to OA treatment. In conclusion, NMDAR and pCREB are involved in memory functions of both the Hip and the MrD. NMDAR might regulate pCREB level in neurons of the MrD but not in the Hip. Hence, the processes and mechanism of learning and memory involved in the MrD and the Hip may be different.


Assuntos
Corpo Estriado/fisiologia , Hipocampo/fisiologia , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Animais , Corpo Estriado/citologia , Hipocampo/citologia , Masculino , Ratos , Ratos Sprague-Dawley
12.
J Biomed Sci ; 20: 9, 2013 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23425148

RESUMO

BACKGROUND: MicroRNAs (miRNAs), a class of highly conserved small non-coding RNA molecules, are known to play essential roles in central nervous system (CNS) by causing post-transcriptional gene silencing. There is much evidence that miRNAs have specific temporal and spatial expression patterns in the mammal brain, but little is known about the role of the region specificity for the gene regulatory networks of the brain. This study represents the first attempt to perform a profiling analysis of the differential expression of miRNAs between hippocampus and the Marginal division (MrD) of the neostriatum in the rat brain. RESULTS: Microarray was used to detect the expression of 357 miRNAs in hippocampus and the MrD from three rats. A short-list of the most dysregulated 30 miRNAs per rat was generated for data analysis, and the miRNAs that were represented in two or three short-lists were then further analyzed. Quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) was employed to validate the aberrantly expressed miRNAs obtained from the miRNA microarray analysis. A family of 11 miRNAs demonstrated differential expression between the MrD and hippocampus in more than one rat. Amongst these, miR-383 was differentially expressed in all three rats and up-regulated to the largest degree in rat one, and the ten other miRNAs, let-7d*, miR-181b, miR-187, miR-195, miR-214, miR-382, miR-411, miR-466b, miR-592 and miR-1224 were differentially expressed in at least two rats. Of these ten, besides miR-382 and miR-411 which were up-regulated in one rat and down-regulated in another, the other eight miRNAs retained a uniform direction of regulation (up-regulation or down-regulation) between different specimens. When further examined by RT-PCR, the aberrantly expressed miRNAs, except miR-383 and let-7d*, demonstrated differential expression that significantly correlated with the microarray findings. CONCLUSION: This study reported that the miRNA expression patterns in MrD was distinct from that of Hip, suggesting the role of miRNAs in the learning and memory function of the MrD probably different from hippocampus.


Assuntos
Hipocampo/metabolismo , Aprendizagem/fisiologia , MicroRNAs/genética , Neostriado/metabolismo , Animais , Regulação para Baixo , Perfilação da Expressão Gênica , Hipocampo/fisiologia , Masculino , Memória/fisiologia , MicroRNAs/metabolismo , MicroRNAs/fisiologia , Neostriado/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Regulação para Cima
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